LONDON: The Bank of England unveiled the design of a new banknote celebrating mathematician Alan Turing, who helped Britain win World War II with his code-breaking skills but is believed to have killed himself after being convicted for having sex with a male partner.
The new £50 (US$69) note features an image of Turing, mathematical formulae from a 1936 paper he wrote that laid the groundwork for modern computer science, and technical drawings for the machines used to decipher the Enigma code.
The polymer note also carries a quote by Turing about the rise of machine intelligence: "This is only a foretaste of what is to come, and only the shadow of what is going to be."
Turing built on work by Polish mathematicians who had discovered how to read Germany's Enigma code, finding a way to crack the Nazis' increased security of the code.
That story was recounted in the 2014 film The Imitation Game in which Turing was played by actor Benedict Cumberbatch.
Turing's work led to the decryption of German naval communications that helped allied convoys steer clear of U-boats and was pivotal in the Battle of the Atlantic.
He also developed a technique that led to the breaking of Germany's more sophisticated Lorenz cypher.
Turing was convicted of gross indecency in 1952 for having sex with a man and underwent chemical castration with injections of female hormones to avoid imprisonment. He lost his security clearance to work with Britain's GCHQ spy agency.
Homosexual sex was illegal in Britain until 1967.
Turing used cyanide to kill himself in 1954, aged 41, according to an inquest at the time. He was granted a royal pardon by Queen Elizabeth in 2013 for the criminal conviction that preceded his death.
"There's something of the character of a nation in its money," BoE Governor Andrew Bailey said in a statement on Thursday (Mar 25), which highlighted the breadth of Turing's accomplishments.
"He was also gay, and was treated appallingly as a result," Bailey said. "By placing him on our new polymer £50 banknote, we are celebrating his achievements, and the values he symbolises."
The head of GCHQ, Jeremy Fleming, said Turing's image on the note was a landmark moment.
"Turing was embraced for his brilliance and persecuted for being gay. His legacy is a reminder of the value of embracing all aspects of diversity, but also the work we still need to do to become truly inclusive," Fleming said.
The BoE said it would fly the rainbow flag from its main building in London's Threadneedle Street on Thursday.
The £50 note is the BoE's highest-value banknote. It will enter circulation on Jun 23, Turing's birthday.